Understanding Chemical Bonds and Electrical Conductivity

National University: Santiago Antunez de Mayolo

Course: General Chemistry

Subject: Introduction to the Periodic System II

School: Agricultural Engineering

Teacher: Victor Martinez Montes

Members:

• Alva Matilla Jesus

1. Title

Chemical Bonding I

2. Aim

• Distinguish how substance properties depend on their type of bond.
• Investigate the linkage present in ionic and covalent substances through the study of electrical conductivity.

3. Theoretical Foundation

The conductivity of a substance is carried by ions—charged particles formed by one or more atoms—excluding metals, whose electrical conduction is not considered in this experiment.

Ionic compounds do not carry current in the solid state, but they do when dissolved or fused, as their crystal lattice releases ions under these circumstances. Conversely, covalent compounds generally do not conduct electric current, except for some solutions that possess ionic character and release ions in aqueous solution, such as acids and bases.

a) Interatomic or Intramolecular Bonds

These bonds join collections of atoms or molecules to form higher-order structures. This category includes ionic, covalent, and metallic bonds.

• Covalent Bond: This type of binding occurs when there is a specific electronegativity difference. It is formed when the electronegativity difference is not large enough for electron transfer to take place; instead, atoms share electron pairs in a new structure called a molecular orbital.
• Coordinate Covalent Bonds (Dative): When a single atom provides the electron pair for the covalent bond, it is termed coordinate or dative. Although the properties are similar to a normal covalent bond, this distinction is useful for tracking valence electrons and assigning formal charges. A base provides the shared electron pair, and an acid accepts it to form the bond, often where an atom does not complete the octet rule.
• Metallic Bond: This is a chemical bond that holds atoms (a union between cations and valence electrons) of metals together. These atoms are grouped closely, resulting in compact, three-dimensional structures known as compact packing of spheres. In this structure, each metal atom is typically surrounded by twelve others (six in the same plane, three above, and three below).